Gunman sought after Russian banker shot in London

British police have released grainy photos of a man suspected of shooting a former Russian banker near London's Canary Wharf financial district, in a case that has raised fears that Russian gangland violence could be spreading to Britain.

Financier German Gorbuntsov, 45, was shot five times as he entered his block of flats near the River Thames on March 20.

He survived the attack but was critically injured and is recovering in hospital where his condition is described as stable.

London's Metropolitan Police have made no arrests and say they are keeping an open mind about the motive.

But unconfirmed British media reports say the inquiry is focusing on organised crime in Russia.

Mr Gorbuntsov had been due to give evidence in an investigation into the attempted murder of a former business associate, his lawyer said last month.

Now police have released grainy security camera images of the man they believe tried to murder Mr Gorbuntsov, who once owned four Russian banks.

The pictures, taken moments after the shooting, show a tall white man wearing a dark hooded top and carrying a bag.

Detectives found a gun, bag and hooded top near the scene.

"We are continuing to examine CCTV footage from the area and are keen to speak with anyone who may have information about the shooting," said Detective Chief Inspector Russell Taylor, who is leading the investigation.

Diplomatic relations between Russia and Britain have been tested by a series of disputes involving Russian emigres.

Russia has refused to extradite the man suspected of murdering former Russian spy Alexander Litvinenko by putting radioactive polonium in his tea in London.